%0 Journal Article
%T Precise Measurement of the Neutrino Mixing Parameter theta(23) from Muon Neutrino Disappearance in an Off-Axis Beam
%A T2K Collaboration (Abe, K. et al
%A Cervera-Villanueva, A.
%A Escudero, L.
%A Izmaylov, A.
%A Monfregola, L.
%A Sorel, M.
%A Stamoulis, P.
%J Physical Review Letters
%D 2014
%V 112
%N 18
%I Amer Physical Soc
%@ 0031-9007
%G English
%F T2KCollaborationAbe_etal2014
%O WOS:000339629400005
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1877), last updated on Wed, 11 Feb 2015 11:56:10 +0000
%X New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter theta(23). Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57 x 10(20) protons on target, T2K has fit the energy-dependent nu(mu) oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(theta(23)) is 0.514(-0.056)(+0.055) (0.511 +/- 0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Delta m(32)(2) = (2.51 +/- 0.10) x 10(-3) eV(2)/c(4) (inverted hierarchy: Delta m(13)(2) = (2.48 +/- 0.10) x 10(-3) eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.
%R 10.1103/PhysRevLett.112.181801
%U http://arxiv.org/abs/1403.1532
%U https://doi.org/10.1103/PhysRevLett.112.181801
%P 181801-8pp